And then lost the war they've started?
Yes, that's a catastrophe for Arabs, just like losing WW2 was a catastrophe for certain Germans. And also for those in Germany who were exiled from their (sometimes extensive) land, no matter what they thought of the war and its outcome.
Eastern Prussian didn't then go and tried to kill the Western German president when the FRG took them in, though. Besides some whining by a few select bunch, that chapter is closed.
Not so for the Arabs for whom the "Nakba" was and is that the military campaign failed and not that Palestinians now live in misery.
"During the foundational events of the Nakba in 1948, dozens of massacres targeting Arabs were conducted and about 400 Arab-majority towns and villages were depopulated;[3] with many of these being either completely destroyed or repopulated by Jewish residents and given new Hebrew names. Approximately 750,000[4] Palestinian Arabs (about half of Palestine's Arab population) fled from their homes or were expelled by Zionist militias and later the Israeli army"
https://en.m.wikipedia.org/wiki/Nakba#:~:text=During%20the%2....
I get why you'd respond to the previous comment, though, which reads as if it's an attempt to deny the events of the Palestinian Nakba. You're right to do that. All I'm here to say is that the 20th century history of that region is complicated and no simple narrative will get anybody to where we are today.
Either way, my only stake in this little subthread is to stick up for the complexity of the history of the region, which both sides of the argument have a tendency to flatten to the point of unrecognizability.